Accounts of Chemical Research最新文献

{"title":"Rational Design of Layered Oxide Materials for Batteries","authors":"Qidi Wang*,&nbsp;Chenglong Zhao and Marnix Wagemaker,&nbsp;","doi":"10.1021/acs.accounts.5c0007410.1021/acs.accounts.5c00074","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00074https://doi.org/10.1021/acs.accounts.5c00074","url":null,"abstract":"<p >Layered transition metal (TM) compounds are pivotal in the development of rechargeable battery technologies for efficient energy storage. The history of these materials dates back to the 1970s, when the concept of intercalation chemistry was introduced into the battery. This process involves the insertion of alkali-metal ions between the layers of a host material (e.g., TiS₂) without causing significant structural disruption. This breakthrough laid the foundation for Li-ion batteries, with materials like LiCoO₂ becoming key to their commercial success, thanks to their high energy density and good stability. However, despite these advantages, challenges remain in the broader application of these materials in batteries. Issues such as lattice strain, cation migration, and structural collapse result in rapid capacity degradation and a reduction in battery lifespan. Moreover, the performance of batteries is often constrained by the properties of the available materials, particularly in layered oxide materials. This has driven the exploration of materials with diverse compositions. The relationship between composition and structural chemistry is crucial for determining reversible capacity, redox activity, and phase transitions, yet predicting this remains a significant challenge, especially for complex compositions.</p><p >In this Account, we outline our efforts to explore rational principles for optimal battery materials that offer a higher performance. The core of this is the concept of ionic potential, a parameter that measures the strength of the electrostatic interaction between ions. It is defined as the ratio of an ion’s charge to its ionic radius, offering a quantitative way to evaluate interactions between cations and anions in crystal structures. By building on this concept, we introduce the cationic potential, which is emerging as a crystallographic tool that captures critical interactions within layered oxide materials. This approach provides insights into structural organization, enabling the prediction of P2- and O3-type stacking arrangements in layered oxides. A key advantage of using the cationic potential is its ability to guide the rational design of electrode materials with improved performance. For example, introducing P-type structural motifs into the material framework can significantly enhance ion mobility, mitigating detrimental phase transitions that often compromise battery efficiency and longevity. Furthermore, ionic potential serves as a representative parameter to quantitatively describe the properties of various TM compositions, providing a straightforward calculation method for designing multielement systems. We anticipate that this Account will provide fundamental insights and contribute to significant advancements in the design of layered materials, not only for battery applications but also for broader fields that require control of the material properties.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 11","pages":"1742–1753 1742–1753"},"PeriodicalIF":16.4,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.accounts.5c00074","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing Light-Driven Reactions with Surface-Modified Optical Fibers.","authors":"Zhe Zhao, Han Fu, Li Ling, Paul Westerhoff","doi":"10.1021/acs.accounts.5c00022","DOIUrl":"10.1021/acs.accounts.5c00022","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusThe challenge of optimizing decentralized water, wastewater, and reuse treatment systems calls for innovative, efficient technologies. One advancement involves surface-modified side-emitting optical fibers (SEOFs), which enhance biochemical and chemical light-driven reactions. SEOFs are thin glass or polymeric optical fibers with functionalized surfaces that can be used individually or bundled together. They can be attached to various light sources, such as light-emitting diodes (LEDs) or lasers, which launch ultraviolet (UV) or visible light into the fibers. This light is then emitted along the fiber's surface, creating irradiance similar to a glow stick. The resulting SEOFs uniquely deliver light energy to complex environments while maximizing photon utilization and minimizing energy loss, addressing long-standing inefficiencies in photolysis and photocatalysis systems. SEOFs generate and leverage refracted light and evanescent waves to achieve continuous irradiation of their cladding, wherein photocatalysts are embedded. This method contrasts with traditional slurry-based systems, where light energy is often scattered or absorbed before reaching the reaction sites. Such scattering typically reduces quantum yields and reaction kinetics. In contrast, SEOFs create a controlled light delivery system that enhances reaction efficiency and adaptability to diverse applications.Important chemical and physical concepts are explored when scaling up SEOFs for three potential engineered applications. The selection of polymer materials and nanoparticle compositions is crucial for optimizing SEOFs as waveguides for visible to UV-C wavelengths and for embedding surface-accessible photocatalysts within porous polymer coatings on SEOF surfaces. Additionally, understanding how light propagates within SEOFs and emits along their exterior surface and length is essential for influencing the quantum yields of chemical products and enhancing biochemical sensitivity to low UV-C exposure. UV-C SEOFs are employed for germicidal disinfection, inactivating biofilms and pathogens in water systems. By overcoming UV light attenuation issues in traditional methods, SEOFs facilitate uniform distribution of UV-C energy, disrupting biofilm formation at early stages. SEOFs enhance UV-A and visible-light photocatalytic degradation of pollutants. Embedding photocatalysts in porous polymer cladding enables simultaneous improvements in reaction kinetics and quantum yields. SEOFs enable decentralized light-driven production of clean energy resources such as hydrogen, hydrogen peroxide, and formic acid, offering sustainable alternatives for off-grid systems.The design principles of SEOFs emphasize scalability, flexibility, and efficiency. Recent innovations in polymer chemistry, nanoparticle coatings, and surface roughness engineering have further optimized light delivery and side-emission. Tailoring the refractive index and nanoparticle distribution on fiber surfaces e","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":" ","pages":"1596-1606"},"PeriodicalIF":16.4,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fundamental Principles in Catalysis from Mechanistic Studies of Oxidative Decarboxylative Coupling Reactions.","authors":"Jessica M Hoover","doi":"10.1021/acs.accounts.5c00142","DOIUrl":"10.1021/acs.accounts.5c00142","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusOxidative decarboxylative coupling (ODC) reactions have been recognized as powerful alternatives to traditional cross-coupling reactions due to the ability to generate (hetero)biaryl structures from simple and readily available carboxylic acid precursors. These reactions, however, are underdeveloped due to the requirement for &lt;i&gt;ortho&lt;/i&gt;-nitrobenzoate coupling partners and silver salts as oxidants. Our research program has focused on the development of new catalytic ODC reactions, as well as mechanistic studies of these reactions to uncover the origin of these synthetic limitations. As the framework for these studies, we explored two key ODC reactions developed in our group: (1) a Ni-catalyzed decarboxylative arylation reaction that relies on silver as the oxidant and (2) a Cu-catalyzed decarboxylative thiolation reaction capable of operating under aerobic conditions. Our findings, disclosed in this Account, have uncovered the importance of the &lt;i&gt;ortho&lt;/i&gt;-substituent and revealed that Ag-based oxidants are also responsible for mediating the decarboxylation and transmetalation steps.Systematic exploration of the decarboxylation of a series of well-defined Ag-benzoate complexes allowed us to probe the importance of the &lt;i&gt;ortho&lt;/i&gt;-nitro group in the decarboxylation step. Kinetic measurements of a large series of differently substituted benzoates were found to correlate with the field effect (&lt;i&gt;F&lt;/i&gt;) of the &lt;i&gt;ortho&lt;/i&gt;-substituent, revealing this feature to be responsible for the enhanced reactivity of these favored benzoates.Our studies of the Ni-catalyzed decarboxylative arylation reaction uncovered an unexpected redox transmetalation step in this system. Synthesis and isolation of the proposed nickelacycle and Ag-aryl intermediates enabled direct study of the fundamental coupling steps. Catalytic and stoichiometric reactions of these complexes, paired with DFT calculations, supported a redox transmetalation step in which the Ag-aryl intermediate transfers the aryl ligand from Ag&lt;sup&gt;I&lt;/sup&gt; to Ni&lt;sup&gt;II&lt;/sup&gt; with concomitant oxidation to generate a Ni&lt;sup&gt;III&lt;/sup&gt;-bis(aryl) intermediate.Finally, detailed mechanistic studies of our Cu-catalyzed decarboxylative thiolation reaction demonstrated how this catalyst system is able to use O&lt;sub&gt;2&lt;/sub&gt; as the terminal oxidant. Kinetic studies paired with the synthesis and reactivity of well-defined copper intermediates revealed decarboxylation from a Cu&lt;sup&gt;I&lt;/sup&gt;-benzoate resting state, despite the oxidizing reaction conditions which could support higher oxidation state intermediates. We also identified the intermediacy of diphenyl disulfide (PhSSPh) formed from the thiophenol (PhSH) coupling partner under the aerobic Cu-catalyzed conditions. The reaction of PhSSPh with the catalyst proceeds via oxidative transfer of the PhS fragment to Cu&lt;sup&gt;I&lt;/sup&gt; that is analogous to that of the redox transmetalation observed in Ni-catalyzed decarboxylative arylation.These studies combined","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":" ","pages":"1670-1682"},"PeriodicalIF":16.4,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rational Design of Layered Oxide Materials for Batteries","authors":"Qidi Wang, Chenglong Zhao, Marnix Wagemaker","doi":"10.1021/acs.accounts.5c00074","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00074","url":null,"abstract":"Layered transition metal (TM) compounds are pivotal in the development of rechargeable battery technologies for efficient energy storage. The history of these materials dates back to the 1970s, when the concept of intercalation chemistry was introduced into the battery. This process involves the insertion of alkali-metal ions between the layers of a host material (e.g., TiS₂) without causing significant structural disruption. This breakthrough laid the foundation for Li-ion batteries, with materials like LiCoO₂ becoming key to their commercial success, thanks to their high energy density and good stability. However, despite these advantages, challenges remain in the broader application of these materials in batteries. Issues such as lattice strain, cation migration, and structural collapse result in rapid capacity degradation and a reduction in battery lifespan. Moreover, the performance of batteries is often constrained by the properties of the available materials, particularly in layered oxide materials. This has driven the exploration of materials with diverse compositions. The relationship between composition and structural chemistry is crucial for determining reversible capacity, redox activity, and phase transitions, yet predicting this remains a significant challenge, especially for complex compositions.","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"28 5 1","pages":""},"PeriodicalIF":18.3,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144096963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rational Approaches toward the Design and Synthesis of Carbon Nanothreads","authors":"Morgan Murphy, Amal Mohamed, John V. Badding, Elizabeth Elacqua","doi":"10.1021/acs.accounts.5c00172","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00172","url":null,"abstract":"Carbon-based materials─often with superlative electronic, mechanical, chemical, and thermal properties─are often categorized by dimensionality and hybridization. Most of these categories are produced in high-temperature conditions that afford equilibrium-dictated structures, but limit their diversity. In contrast, an emerging class of one-dimensional (1D) carbon materials, coined nanothreads, are accessible through kinetically controlled solid-state reactions of small multiply unsaturated molecules. While abundant in molecular organic synthesis, exerting kinetic control over reactivity is a revolutionary approach to access dense carbon networks. Owing to their internal diamond-like core, these materials are calculated to span a wide range of mechanical and optical properties, with the introduction of functional groups and/or heteroatoms leading to tailorable band gaps and the potential to access electronic states that are not featured in traditional polymers or nanomaterials. Accessing these properties requires the ability to precisely control solid-state molecular reaction pathways, chemical connectivity, and heteroatom/functional group density. Carbon nanothreads are often synthesized through the pressure-induced polymerization of aromatic molecules (e.g., benzene, pyridine, and thiophene) upon compression to 23–40 GPa. While the high pressures required to achieve these crystalline materials often preclude making synthetically viable quantities of product, the use of lessened aromatic reactants, along with light and/or heat, enables more mild reaction pressures. Success to date in forming nanothreads from diverse reactants suggests that physical organic principles govern the reaction, along with topochemical relationships, enabling the emergence of a new field of carbon chemistry that combines the control of organic chemistry with the range of physical properties only possible in extended periodic solids.","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"11 1","pages":""},"PeriodicalIF":18.3,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144096965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Motif-Directed Oxidative Folding to Design and Discover Multicyclic Peptides for Protein Recognition.","authors":"Chuanliu Wu","doi":"10.1021/acs.accounts.5c00060","DOIUrl":"10.1021/acs.accounts.5c00060","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusMulticyclic peptides that are constrained through covalent cross-linkers can usually maintain stable three-dimensional (3D) structures without the necessity of incorporating noncovalently interacting cores. This configuration allows for a greater utilization of residues for functional purposes compared to larger proteins, rendering multicyclic peptides attractive molecular modalities for the development of chemical tools and therapeutic agents. Even smaller multicyclic peptides, which may lack stable 3D structures due to limited sequence-driven folding capabilities, can still benefit from the specific conformations stabilized by covalent cross-linkers to facilitate target binding. Disulfide-rich peptides (DRPs) are a class of particularly significant multicyclic peptides that are primarily composed of disulfide bonds in their interior. However, the structural diversity of DRPs is limited to a few naturally occurring and designer scaffolds, which significantly impedes the development of multicyclic peptide ligands and therapeutics. To address this issue, we developed a novel method that utilizes disulfide-directing motifs to design and discover DRPs with new structures and functions in random sequence space. Compared with traditional DRPs, these new DRPs that incorporate disulfide-directing motifs exhibit more precise oxidative folding regarding disulfide pairing and demonstrate greater tolerance to sequence manipulations. Thus, we designated these peptides as disulfide-directed multicyclic peptides (DDMPs).Over the past decade, we have developed a new class of multicyclic peptides by leveraging disulfide-directing motifs, including biscysteine motifs such as CPXXC, CPPC, and CXC (C: cysteine; P: proline; X: any amino acid), as well as triscysteine motifs that rationally combine two biscysteine motifs (&lt;i&gt;e.g.&lt;/i&gt;, CPPCXC and CPXXCXC) to direct the oxidative folding of peptides. This leads to the introduction of a novel concept known as motif-directed oxidative folding, which is valuable for the construction of peptides with multiple disulfide bonds. A large diversity of DDMPs have been designed by simply altering the disulfide-directing motifs, the arrangement of cysteine residues (&lt;i&gt;i.e.&lt;/i&gt;, cysteine patterns), and the number of random residues separating them. As the oxidative folding of DDMPs is primarily determined by disulfide-directing motifs, these peptides are intrinsically more tolerant of extensive sequence manipulations compared to traditional DRPs. Consequently, multicyclic peptide libraries with an unprecedented high degree of sequence randomization have been developed by utilizing commonly used biological display systems such as phage display. We have validated the applicability of these libraries by successfully discovering DDMPs with unique protein-like 3D structures and high affinity and specificity to various cell-surface receptors, including tumor-associated antigens, immune costimulatory receptors, and G prot","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":" ","pages":"1620-1631"},"PeriodicalIF":16.4,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Organic Photocatalyst Utilizing Triplet Excited States for Highly Efficient Visible-Light-Driven Polymerizations.","authors":"Yonghwan Kwon, Woojin Jeon, Johannes Gierschner, Min Sang Kwon","doi":"10.1021/acs.accounts.4c00847","DOIUrl":"10.1021/acs.accounts.4c00847","url":null,"abstract":"&lt;p&gt;&lt;p&gt;ConspectusUltraviolet (UV) light has traditionally been used to drive photochemical organic transformations, mainly due to the limited visible-light absorption of most organic molecules. However, the high energy associated with UV light often causes undesirable side reactions. In the late 2000s, MacMillan, Yoon, and Stephenson pioneered the use of visible light in conjunction with photocatalysts (PCs) to initiate organic transformations. This innovative approach overcame the limitations of UV light by utilizing visible-light-absorbing PCs in their photoexcited states for electron or energy transfer, generating reactive radical species and promoting the photoreactions. Furthermore, while the photocatalysis has predominantly relied on transition-metal complexes, concerns over the potential toxicity, cost, and sustainability of these metals have driven the development of organic PCs. These organic PCs eliminate the need for metal removal, offer structural diversity, and enable tuning of their properties, thus paving the way for the creation of a tailored library of PCs.In recent decades, significant advancements have been made in the development of novel organic PCs with diverse scaffolds, with a notable example being the work of Zhang et al. in 2016. They demonstrated that cyanoarene analogues, originally developed by Adachi et al. for thermally activated delayed fluorescence (TADF) in organic light-emitting diodes, could function effectively as PCs. Building on these insights, we developed a PC design platform featuring TADF compounds with twisted donor-acceptor structures, which paved the way for new PC discoveries. We showcased these PCs' ability (i) to generate long-lived lowest triplet excited (T&lt;sub&gt;1&lt;/sub&gt;) states and (ii) to tune redox potentials by independently modifying donor and acceptor moieties. Through this platform, we discovered PCs with varying redox potentials and the capability to effectively populate T&lt;sub&gt;1&lt;/sub&gt; states, establishing structure-property relationships within our PC library and creating PC selection criteria for targeted reactions. Specifically, we tailored PCs for highly efficient reversible-deactivation radical polymerizations, including organocatalyzed atom transfer radical polymerization, photoinduced electron/energy transfer reversible addition-fragmentation chain transfer polymerization, and atom transfer radical polymerization with dual photoredox/copper catalysis as well as rapid free radical polymerizations. These advancements have also facilitated the development of functionalized, visible-light-cured adhesives for advanced display technologies. Furthermore, we investigated the origins of the exceptional catalytic performance of these PCs through comprehensive mechanistic studies, including electrochemical and photophysical measurements, quantum chemical calculations, and kinetics simulations. Specifically, we studied the formation and degradation of key PC intermediates in photocatalytic dehaloge","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":" ","pages":"1581-1595"},"PeriodicalIF":16.4,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12096438/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Truncating 2D Framework Materials Down to a Single Pore: Synthetic Approaches and Opportunities","authors":"Phuong H. Le, Leo B. Zasada, Dianne J. Xiao","doi":"10.1021/acs.accounts.5c00171","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00171","url":null,"abstract":"In this Accounts article, we summarize our recent work on truncating conjugated two-dimensional framework materials down to a single pore, or a single macrocycle. Conjugated 2D architectures have emerged as one of the most synthetically adaptable motifs for coupling semiconductivity and porosity in metal–organic frameworks (MOFs) and covalent organic frameworks (COFs). However, despite their prevalence, 2D architectures have several limitations. In particular, the strong interlayer π–π stacking can limit both processability and the accessibility of internal active sites. We have found that simple macrocycles preserve key aspects of 2D framework structure and function, including porosity and out-of-plane electrical conductivity, while providing improved processability, surface tunability, and mass transport properties. In this article, we first describe our synthetic approach and general design considerations. Specifically, we show how ditopic analogues of the tritopic ligands commonly found in the synthesis of 2D MOFs and COFs can be used to achieve a diverse library of conjugated macrocycles that resemble fragments of semiconducting frameworks in both form and function. The length of the peripheral side chains, the size of the aromatic core, and the solubility of intermediates are all key variables in favoring selective macrocycle formation over undesired linear polymers and oligomers. Next, we highlight the unique advantages that macrocycles provide, including improved processability, atomically precise surface tunability, and greater active site accessibility. In particular, the identity of the peripheral side chains dramatically impacts both solubility and colloidal stability as well as crystal size and morphology. We further show how the solution processability and nanoscale dimensions of macrocycles can simplify electronic device fabrication and improve electrochemical performance. Finally, we end with a forward-looking discussion on how macrocycles offer a unique bridge between conjugated molecules and extended frameworks, enabling new application areas and fundamental science.","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"55 1","pages":""},"PeriodicalIF":18.3,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144096966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Truncating 2D Framework Materials Down to a Single Pore: Synthetic Approaches and Opportunities","authors":"Phuong H. Le,&nbsp;Leo B. Zasada and Dianne J. Xiao*,&nbsp;","doi":"10.1021/acs.accounts.5c0017110.1021/acs.accounts.5c00171","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00171https://doi.org/10.1021/acs.accounts.5c00171","url":null,"abstract":"<p >In this Accounts article, we summarize our recent work on truncating conjugated two-dimensional framework materials down to a single pore, or a single macrocycle. Conjugated 2D architectures have emerged as one of the most synthetically adaptable motifs for coupling semiconductivity and porosity in metal–organic frameworks (MOFs) and covalent organic frameworks (COFs). However, despite their prevalence, 2D architectures have several limitations. In particular, the strong interlayer π–π stacking can limit both processability and the accessibility of internal active sites. We have found that simple macrocycles preserve key aspects of 2D framework structure and function, including porosity and out-of-plane electrical conductivity, while providing improved processability, surface tunability, and mass transport properties. In this article, we first describe our synthetic approach and general design considerations. Specifically, we show how ditopic analogues of the tritopic ligands commonly found in the synthesis of 2D MOFs and COFs can be used to achieve a diverse library of conjugated macrocycles that resemble fragments of semiconducting frameworks in both form and function. The length of the peripheral side chains, the size of the aromatic core, and the solubility of intermediates are all key variables in favoring selective macrocycle formation over undesired linear polymers and oligomers. Next, we highlight the unique advantages that macrocycles provide, including improved processability, atomically precise surface tunability, and greater active site accessibility. In particular, the identity of the peripheral side chains dramatically impacts both solubility and colloidal stability as well as crystal size and morphology. We further show how the solution processability and nanoscale dimensions of macrocycles can simplify electronic device fabrication and improve electrochemical performance. Finally, we end with a forward-looking discussion on how macrocycles offer a unique bridge between conjugated molecules and extended frameworks, enabling new application areas and fundamental science.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"58 11","pages":"1776–1785 1776–1785"},"PeriodicalIF":16.4,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population Balance Models for Catalytic Depolymerization: From Elementary Steps to Multiphase Reactors.","authors":"Lela K Manis,Jiankai Ge,Changhae Andrew Kim,Emmanuel Ejiogu,Ziqiu Chen,Ryan D Yappert,Baron Peters","doi":"10.1021/acs.accounts.5c00088","DOIUrl":"https://doi.org/10.1021/acs.accounts.5c00088","url":null,"abstract":"ConspectusThe ongoing accumulation of plastic waste in landfills and in the environment is driving research on chemical processes and catalysts to recycle polymers. Traditional modeling strategies are not applicable to these processes because they involve too many reactants and intermediates, one for each molecular weight and each functionalization. To model the kinetics, we have developed population balance models (PBMs) that account for macromolecular reactants in the bulk and macromolecular catalytic intermediates. These PBMs couple to each other through polymer adsorption and desorption models and to traditional rate equations for small molecule products and co-reactants (like hydrogen or ethylene). The models, in combination with experimental data, are being used in many ways: (i) to test mechanistic hypotheses, (ii) to extract rate parameters, (iii) to quantitatively compare catalyst activities, (iv) to account for mass transfer and vapor-liquid partitioning in two-phase reactors, and (v) to design novel support architectures and catalysts that mimic the processive action of natural depolymerization enzymes. Some key theoretical advances allow PBMs to be constructed from elementary rates and mechanisms, as opposed to traditional formulations with pseudoelementary rate parameters invoked as fitting parameters. We discuss ways to build these models \"bottom-up\" from first-principles calculations and ways to extract model parameters from \"top down\" analyses of rate data. The combination provides a quantitative bridge between first-principles calculations and the kinetics of complex macromolecular transformations for polymer upcycling and beyond.","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":"5 1","pages":""},"PeriodicalIF":18.3,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144065612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}